The invention relates to a fluid line connection safeguard for axial connection of a socket-shaped end portion of a first fluid line part with an end portion of a second fluid line part formed as a spigot end, wherein the fluid line connection safeguard comprises an annular clamping body which has a through opening with an overall internal contour adapted to the external diameter of the second fluid line part for insertion of the second fluid line part, wherein at least one hook-shaped retaining element extending in the axial direction for engagement with the end portion of the first fluid line part is formed on the clamping body, wherein at least one stem-like spacer extending in the axial direction is formed on the clamping body, and wherein the at least one retaining element and the at least one spacer extend in the same axial direction.
The invention also relates to a socket connection which has a first fluid line part with a socket-shaped end portion, a second fluid line part with an end portion formed as a spigot end, and a fluid line connection safeguard, wherein the end portion of the second fluid line part formed as a spigot end can be inserted into the socket-shaped end portion of the first fluid line part, and the socket-shaped end portion of the first fluid line part has on its end face at least one collar-like projection formed at least partially on the circumference, wherein the fluid line connection safeguard comprises an annular clamping body with a through opening having an overall internal contour adapted to the external diameter of the second fluid line part for insertion of the second fluid line part, wherein in an assembled arrangement of the socket connection the end portion of the second fluid line part is inserted into the end portion of the first fluid line part and the fluid line connection safeguard is pushed over the outer wall of the second fluid line part and is arranged in the vicinity of the socket-shaped end portion of the first fluid line part, wherein at least one hook-shaped retaining element extending in the axial direction is formed on the annular clamping body for engagement behind the collar-shaped projection formed on the end portion of the first fluid line part, wherein in an assembly position of the socket connection the at least one retaining element engages behind the collar-shaped projection in such a way that the annular clamping body tilts in a deviation from a crooked or oblique position directed perpendicular to the axial direction and bears against the outer wall of the second fluid line part by positive engagement, wherein at least one stem-like spacer extending in the axial direction is formed on the clamping body and, in an assembly position of the socket connection, is supported on the collar-shaped projection of the socket-shaped end portion of the first fluid line part, and wherein the at least one retaining element and the at least one spacer extend in the same axial direction.
In the context of the invention the expression “fluid line part” covers any types of tubular shaped piece or shaped parts in pipelines, such as for example pipes, pipe bends, T-pieces, Y-pieces, coupling sleeves, U-pipes, pipe branches, reductions, pipe stubs and the like. Therefore, statements below relating to pipes, pipelines and pipe joints should not be understood as restricted to pipes but generally to above-mentioned types of fluid line parts and connections thereof. Likewise, in the context of the invention the expression “fluid” covers both gases and also liquids.
It is generally known for end portions of fluid line parts, such as for example pipes, to be connected to one another in order to forma fluid line or pipeline by means of screw, flange, clamp or socket connections.
In the case of screw connections, the end portions of the pipes or fluid line parts have a thread, so that the end portions of the pipes can be securely connected to one another. However, such screw connections restrict the flexibility of laying pipes to a certain extent and, furthermore, require time-consuming fitting operations. Therefore, such screw connections are usually used only in the pipes with small nominal widths, and for nominal pressures up to several hundreds of bars.
In the case of greater nominal widths of the pipe or fluid line parts, flange connections are used in order to connect pipe sections in a sealed but releasable manner. For sealing of the flange connection the contact pressure of the sealing surfaces on the interposed seal is crucial. The contact pressure is generally applied by screws which are inserted through holes in the flange leaves. These flange leaves or flanges are usually welded to the pipe, which entails complex welding work.
In the case of clamp connections, the end portions the pipes or fluid line parts to be connected are completely surrounded by a clamping body. By means of one or more screw connections the clamping body is then tightened and thus clamps the end portions of the pipes to be connected, wherein the region to be clamped comprises almost 360° comprises and the surface pressure between the pipe and the clamping body builds up uniformly. In this case the permissible tightening torque of the screws must be observed in order to achieve the necessary frictional grip between the clamping body and the pipes, so that sealing of the connection is ensured.
Furthermore, socket connections for uninterrupted connection of pipes or fluid line parts are known from the prior art. Such socket connections are used both for substantially pressureless pipelines, such as for example sewer pipes or cable conduits, and also for pressurized pipelines, such as for example conduits for gas, exhaust gas, drinking water or waste water. The socket connection has a socket element which can be produced, for example, by widening of an end portion of a pipe. Alternatively, the socket element can be formed as a separate slip-on socket and can be fitted on the end portion of the pipe. This socket connection is also designated as a so-called push-in socket connection in which a free end portion of a pipe is inserted into the socket element, wherein the free end portion of the pipe is generally designated as a spigot end. For sealing the socket connection, a sealing ring is usually provided, which is inserted in a circumferential groove formed in the inner wall of the socket element.
A disadvantage of these socket connections is that they are not generally self-locking and are not designed to withstand tensile forces, so that there is risk that when tensile loading takes effect the pipes or fluid line parts to be connected slide apart and release the pipe connection or fluid line connection.
In order to prevent this, push-in socket connections are known in which for the purpose of securing the pipe connection before the sealing ring an annular clamping element is arranged in a special recess running all round, and under the action of the recess which narrows towards the socket inlet the clamping element is pressed against the spigot end and, by friction, prevents the spigot end from moving out of the socket. In this case the clamping ring can in particular be roughened or toothed. However, it is a disadvantage that visual checking of the security in the form of the clamping ring is not possible, since the clamping ring is arranged in the interior of the pipe connection between the pipes and checking is only possible when the pipe connection is released.
Furthermore, the use of such a clamping element has the disadvantage that the clamping element does not take effect immediately, but only after a certain run-up distance, so that sealing of the connection is not guaranteed in every case. In addition, such generally elastic clamping elements only withstand a certain tensile force and are not suitable for greater tensile loads. Thus in particular in the case of pressurized socket connections there is a risk that the socket connection is released under tensile loading. Furthermore, in some countries there are strict and mandatory requirements that the socket connection must withstand, for example, a tensile loading of several hundred Newtons as well as a predetermined torque acting on the connection.
These requirements are met by a socket connection of the type designated in the introduction, which is known from EP 2 354 615 B1, which furthermore describes a fluid line connection safeguard of the type designated in the introduction which withstands high tensile forces. However, this fluid line connection safeguard has the disadvantage that it is designed only for a single nominal width of the fluid line part and thus can only be used for an application with a specific nominal width.
The object of the invention is to create a solution which, in a structurally simple and cost-effective manner, provides a simplified and improved safeguard for axial connection of end portions of fluid line parts, which furthermore can be easily fitted and disengaged, is effective immediately after application and can be used for different nominal widths.
In the case of a fluid line connection safeguard and a socket connection of the type designated in the introduction this object is achieved according to the invention in that at least two clamping body elements form the clamping body, wherein a respective clamping body element has a circular segment-shaped internal contour and the circular segment-shaped internal contour of the at least two clamping body elements form the overall internal contour, and wherein the at least two clamping body elements should be connected to one another by means of an adjusting connection in such a way that the overall internal contour is adjustable to at least two different diameters.
Advantages and expedient embodiments and modifications of the invention are disclosed by the corresponding sub-claims.
The invention provides a possibility by which an increase in the tensile strength for fluid line connections such as, for example, pipe joints, like a push-in socket connection, is achieved in a structurally simple manner. The fluid line connection safeguard serves for quick connection of end portions of fluid line parts, such as for example pipes. With the aid of the fluid line connection safeguard according to the invention it is now possible to produce not only a tension-resistant fluid line connection or pipe connection, but also to release it again in a simple manner. Because at least two clamping body elements form the clamping body and are connected to one another by means of an adjusting connection, it is possible to use the fluid line connection safeguard not only for connection of a specific nominal width, but also to use the fluid line connection safeguard for another application with another nominal width. Furthermore, the resulting flexibility for use of the fluid line connection safeguard is reflected in a reduction in the production and purchase costs, as it is no longer necessary to purchase a specific fluid line connection safeguard for a specific nominal width. Instead, the fluid line connection safeguard according to the invention covers at least two nominal widths. In this case it is not necessary to align the spacer and the retaining element strictly parallel to one another. Furthermore, due to the oblique position of the fluid line connection safeguard in the fitted state or in the assembled arrangement, a slight clamping or pre-clamping of the clamping body on the second fluid line part is achieved. This clamping causes the fluid line connection safeguard to tilt further in the event of any sliding apart of the fluid line connection and thus ultimately a type of self-locking occurs. The fitting of the fluid line connection safeguard or the socket connection can take place quickly by hand without the use of a tool. Furthermore, the fluid line connection is not subject to any influence by a technician or workman. Since the connection according to the invention does not use any screws, flanges, clips or the like, there is also no need to pay attention to tightening torques of the screws. Checking whether the fluid line connection is properly set up and the fitting of the fluid line connection safeguard has taken place correctly can be carried out by means of simple visual inspection.
In a modification of the fluid line connection safeguard according to the invention the axial length or extent of the at least one hook-shaped retaining element is greater than the axial length or extent of the at least one stem-like spacer. These measure additionally supports the clamping or tilting of the fluid line connection safeguard on the second fluid line part, wherein the spacer in the installation position of the fluid line connection safeguard is supported on the projection of the end portion of the first fluid line part, whereas the hook-shaped retaining element engages behind a projection formed on the end portion of the first fluid line part. This is the same projection which runs all round circumferentially on the socket-shaped end portion of the fluid line part. However, it is also conceivable that two projections on the socket-shaped end portion are formed on parts of the circumference of the end portion and the arrangement thereof corresponds to the arrangement of the retaining element and the spacer.
In an embodiment of the fluid line connection safeguard according to the invention it is particularly advantageous if the clamping body is formed by a first clamping body element and a second clamping body element which are in each case circular segment-shaped, wherein at least two insertion recesses are formed on a first circular segment end of the first clamping body element, wherein an adjustment slot is formed on a second circular segment end of the first clamping body element, wherein a retaining hook, which in the assembled state of the clamping body engages in one of the at least two insertion recesses of the first clamping body element, is formed on a first circular segment end of the second clamping body element, and wherein on a second circular segment end of the second clamping body a T-shaped adjustment means is formed, which in the assembled state of the clamping body protrudes into the adjustment slot and is fixed against movement at one of two end regions of the adjustment slot. Consequently, the adjusting connection is formed by the insertion recesses, of which one co-operates with the retaining hook, and one of the end regions of the adjustment slot in which the adjustment means is fixed. Because the retaining hook engages in one of the insertion recesses and the adjustment means is fixed in one of the end regions of the adjustment slot a purely mechanical connection is produced, which functions without screws or other aids, in order to produce a secure and reliable connection, so that no tool has to be used for fitting the two clamping body elements, which significantly simplifies the fitting.
In a further embodiment of the fluid line connection safeguard according to the invention the width of the adjustment slot is smaller than the width of the stem of the T-shaped adjustment means leading to the top member, wherein the depth of the stem of the T-shaped adjustment means leading to the top member corresponds substantially to the width of the adjustment slot, wherein the two end regions of the adjustment slot are larger than the width of the stem of the T-shaped adjustment means leading to the top member, and wherein the second clamping body element is rotatable relative to the first clamping body element when the stem of the T-shaped adjustment means leading to the top member is arranged inside one of the two end regions of the adjustment slot. Due to this configuration the adjustment means can be fixed to the first clamping body element in a defined manner only in the end regions, whereas the adjustment slot allows a movement of the adjustment means from end region to end region, but fixing of the adjustment means along the adjustment slot is not possible.
With regard to cost-effective manufacture of the fluid line connection safeguard it is advantageous in one embodiment of the invention if the at least one retaining element and the at least one spacer are formed on the first clamping body element.
In order to ensure the stability of the assembled clamping body elements, in a further embodiment according to the invention the at least one retaining element is formed on the first circular segment end of the first clamping body element. The at least one retaining element is preferably arranged between the at least two insertion recesses.
In addition to ensuring the stability of the assembled clamping bodies, in a further embodiment the at least one spacer is formed on the second circular segment end of the first clamping body element. Here too it is preferred that the at least one spacer is arranged between the two end regions of the adjustment slot.
For reasons of the stability of the fluid line connection safeguard, in one embodiment according to the invention in the assembled clamping body the T-shaped adjustment means and the retaining hook of the second clamping body element point in the same axially direction as the at least one retaining element and the at least one spacer which are formed on the first clamping body element.
In order to increase the clamping action of the fluid line connection safeguard on the outer circumference of the second fluid line part, it is advantageous that the clamping body—in particular in the assembly position of the socket connection—is arranged with a certain pre-clamping effect on the second fluid line part. In addition to this certain pre-clamping, according to one embodiment of the invention the internal contour of the through opening of the clamping body is sharp-edged or is formed as a friction surface, in order to increase the clamping or tilting of the fluid line connection safeguard on the outer wall of the fluid line part. For example, in the case of a metal construction of the fluid line connection safeguard the sharp-edged internal contour of the clamping body can easily cut into the outer wall of a fluid line part made, for example, of plastic, which additionally increases the clamping action.
Furthermore, according to an embodiment of the invention the axial width of the projection is greater than the amount of the difference between the axial lengths of the at least one retaining element and the at least one spacer. This results in a controlled oblique positioning and certain pre-clamping or tilting of the fluid line connection safeguard on the outer wall of the fluid line part.
In a modification according to the invention the at least one spacer is formed substantially on the side of the clamping body radially opposite the at least one retaining element. However, it is also conceivable to arrange the spacer at a different position and/or to provide a plurality of spacers. These different embodiments ensure that the fluid line connection safeguard in its installation position or in the assembled arrangement of the fluid line connection is arranged slightly tilted on the second fluid line part and bears closely against the outer wall of the second fluid line part.
Finally, in an embodiment of the invention, in the assembled arrangement of the socket connection the fluid line connection safeguard is tilted at an angle between 5° and 10° with respect to the axis extending perpendicular to the axial direction of the socket connection. with the second fluid line part on its outer wall. This angular range ensures a sufficient clamping action in order to prevent the fluid line parts from sliding apart. However, it is also conceivable that an angle of less than 5° as well as an angle of more than 10° can be used, which for example depends, amongst other things, upon the diameter of the fluid line parts to be connected.
It will be understood that the features referred to above and still to be explained below can be used not only in the respective combination stated but also in other combinations or by themselves without departing from the scope of the present invention. The scope of the invention is defined only by the claims.
Further details, features and advantages of the invention are apparent from the following description in connection with the drawings, in which a preferred exemplary embodiment of the invention is illustrated by way of example.